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For the following questions (not multiple choice) involving calculations, be sure to show your work and include units. No credit is given if work is not shown. 1. 3 points. Answer the following questions for 2.50L of pure water. (Hint: the density of water is 1.00g/mL ) a. How many water molecules are in 2.50L of water? b. How many hydrogen atoms are in 2.50L of water? 2. 1 point. How many oxygen atoms are in 1500 molecules of C6H12O6. 3. 2 points. Write and balance a chemical equation for the combustion of C2H5OH 4. 3 points. Calculate the mass of CO2 produced in the combustion of 3.0gC2H5OH (Hint: use the balanced reaction you wrote in question 3) 5. 1 point. Calculate the percent by mass of carbon in C2H5OH